This invention relates to an improvement in an apparatus for dispensing a strip material, i.e. tape, ribbon, web, string or the like, generally referred to hereinafter as “tape” or “strip material”, when the tape is being unwound at a laminating machine such as a corrugating machine or press. One aspect of the present invention is to prevent the tape from falling off the edge of the tape package when unwinding. Another aspect is to prevent the tape from twisting in the dispensing equipment.
Reinforcing or tear tapes have been used for many years in modern packaging as an aid to maintain structural integrity or as an easy open feature in boxes, packages and/or containers. One limitation of the dispensing equipment used at the laminating machine is the difficulty to prevent the tape from falling off the edge of the tape package. To be able to put a reasonable amount of linear footage on a tape package, the use of a cross winding principle is mandatory. Therefore, for a tape with a width of ½ inch, the tape package can be 13 to 18 inch wide, with a diameter up to 18 inches. As a result, the tape is wound on the package with a traverse pattern so that when the tape is wound around a spindle or core, the tape is also moved in a back and forth motion along the length of the spindle or core. The ratio between the number of revolutions of the spindle over the stroke of the tape along the length of the spindle is known as the winding ratio. Since the tape can be slippery at room temperature, there is a danger that, when the tape reaches the edge of the tape package and stays there until it changes direction to go back toward the middle of the package, it can come off the edge of the tape package and fall off down to the spindle of the tape package. When that happens, the tape cannot go back to the delivering surface of the tape package and the package will stop delivering tape with the undesirable result that the tape breaks.
To prevent the tape from coming or falling off the edge of the tape package, the tape industry has used different techniques such as: adhesive formulation providing added tack between the layers of the tape package, faster winding ratios to try to limit the amount of time when the tape is positioned near the edge of the tape package, roll flanges made of hard materials or paper coated with pressure sensitive adhesives placed on the edges of the tape package to create a physical barrier to prevent the tape from falling off the edge of the tape package, and so on. Each of these techniques have their drawbacks which can reduce tape performance at the laminating machine. For example, increasing the tack of the adhesive formulation of the tape can diminish the performance of the tape in the laminating process or can cause other tape dispensing problems such as pulleys becoming gummed with adhesive deposits coming from the adhesive of the tape. Another example is the tape that can be damaged by the physical barrier on the edges of the tape package, when the physical barrier rubs on the sides of the tape during shipment.
The literature is abundant with tape dispenser systems and tape splicing systems for unwinding tape packages at laminating machines or presses. Often the literature is describing splicing system, as all tape must be fed to continuously running processes and since all tape packages contain a very limited amount of linear footage, the splicing feature becomes a critical element. We can see this in the following patents (or application): U.S. Pat. No. 4,917,327; U.S. Pat. No. 5,029,768; U.S. 2002/0059982; U.S. Pat. No. 6,325,324; U.S. Pat. No. 5,775,629 and U.S. Pat. No. 6,622,959. It would be evident to someone outside this industry that the simplest way to diminish the criticality of the splicing system would be to increase the amount of linear footage on a tape package. But as the industry is well aware, one of the main reason why tape packages are not made larger is that as the diameter of the tape package increases, the amount of time that the tape stays at the edge of the package increases, thus increasing the dangers of having tape fall offs to a point where it becomes a major problem. This invention solves this problem, as any increases in the tape package diameter does not increase the occurrence of fall offs.